1. Field of the Invention
This invention relates to an axial mini ventilator which has an air conduction housing with a ring-shaped flow channel, with an impeller wheel which is located on the suction-side end of the flow channel, completely inside the air conduction housing, and with several permanently installed air baffles which extend radially in the flow channel and have curved tip and root lines.
2. Description of the Prior Art
The prior art includes numerous models of ventilators or fans of this type. For example, U.S. Pat. No. 4,603,271 discloses a ventilator which, as illustrated in FIG. 7, has blade rows on both sides of the impeller wheel. The blades form baffles curved in a circular fashion which extend radially in a ring-shaped flow channel and which are used to create the most laminar axial air flow possible through the flow channel. Such ventilators are called axial ventilators, since the air flows through the flow channel essentially coaxially with respect to the axis of the rotor.
If such mini ventilators are to be used as built-in ventilators, for example ventilators which are incorporated in a medical device or in a dental treatment instrument, these mini ventilators must meet special requirements. Since these ventilators are, as a rule, powered by an electric battery, they must achieve the longest possible operating time with the highest possible efficiency from each battery. During operation, the levels of noise generated and heat produced should also be as low as possible.
The object of the invention is to create a ventilator of the type described above which comes significantly close to meeting the requirements indicated above and which can still be manufactured economically.